Q
What is the primary difference between const and let in JavaScript?

Answer & Solution

Answer: Option B
Solution:
The primary difference is that const variables are block-scoped, meaning they are only accessible within the block they are defined in, while let variables are mutable.
Related Questions on Average

What does the const keyword signify in JavaScript?

A). A. Constant variable

B). B. Mutable variable

C). C. Global variable

D). D. Block-scoped variable

Which statement is true regarding the const keyword in JavaScript?

A). A. Constants declared with const are hoisted

B). B. Constants declared with const can be reassigned

C). C. Constants declared with const have global scope

D). D. Constants declared with const are immutable

What is the purpose of using the const keyword in JavaScript?

A). A. To declare variables with global scope

B). B. To declare block-scoped variables

C). C. To declare variables that can be reassigned

D). D. To declare variables that cannot be reassigned

What is the primary advantage of using block scope in JavaScript?

A). A. Reducing code size

B). B. Preventing variable hoisting

C). C. Avoiding global variables

D). D. Improving performance

Which of the following statements is true about constants declared using const?

A). A. They can be reassigned multiple times

B). B. They are hoisted to the top

C). C. They are mutable

D). D. They are immutable

Which keyword is used to declare a constant array in JavaScript?

A). A. let

B). B. const

C). C. var

D). D. array

What will be the output of the code above?

A). A. [1, 2, 3, 4]

B). B. [1, 2, 3]

C). C. [1, 2, 3, 4, 5]

D). D. Error

What will be the output of the code above?

A). A. 10

B). B. 20

C). C. Error

D). D. Undefined

What happens if you try to reassign a value to a constant declared using const?

A). A. SyntaxError

B). B. TypeError

C). C. ReferenceError

D). D. No error, value is reassigned

What will be logged to the console?

A). A. 'John'

B). B. 'Jane'

C). C. Error

D). D. Undefined